* Copyright: (c) Universitaet Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*
- * NOTE: Comments my be (partially) wrong, since there was a major bug
- * (spilling of phis, prespill) whose fixing changed a lot.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#include "obst.h"
#include "set.h"
#include "pset.h"
+#include "irprintf_t.h"
#include "irgraph.h"
#include "irnode.h"
#include "irmode.h"
#include "irgwalk.h"
#include "iredges_t.h"
#include "ircons_t.h"
+#include "irprintf.h"
#include "beutil.h"
#include "bearch.h"
#define DBG_SLOTS 32
#define DBG_TRACE 64
#define DEBUG_LVL 0 //(DBG_START | DBG_DECIDE | DBG_WSETS | DBG_FIX | DBG_SPILL)
-static firm_dbg_module_t *dbg = NULL;
+DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
#define MIN(a,b) (((a)<(b))?(a):(b))
-#undef SINGLE_START_PROJS
typedef struct _workset_t workset_t;
typedef struct _belady_env_t {
struct obstack ob;
- const be_node_factory_t *factory;
const arch_env_t *arch;
const arch_register_class_t *cls;
int n_regs; /** number of regs in this reg-class */
ir_node *instr; /**< current instruction */
unsigned instr_nr; /**< current instruction number (relative to block start) */
pset *used; /**< holds the values used (so far) in the current BB */
+ pset *copies; /**< holds all copies placed due to phi-spilling */
spill_env_t *senv; /* see bespill.h */
pset *reloads; /**< all reload nodes placed */
struct _workset_t {
belady_env_t *bel;
- int i; /**< used for iteration TODO remove this form the struct */
int len; /**< current length */
loc_t vals[1]; /**< inlined array of the values/distances in this working set */
};
-typedef struct _block_info_t {
- workset_t *ws_start, *ws_end;
-} block_info_t;
+void workset_print(const workset_t *w)
+{
+ int i;
+
+ for(i = 0; i < w->len; ++i) {
+ ir_printf("%+F %d\n", w->vals[i].irn, w->vals[i].time);
+ }
+}
/**
* Alloc a new workset on obstack @p ob with maximum size @p max
return 0;
}
-#define workset_foreach(ws, v) for(ws->i=0; \
- v=(ws->i < ws->len) ? ws->vals[ws->i].irn : NULL, ws->i < ws->len; \
- ws->i++)
+/**
+ * Iterates over all values in the working set.
+ * @p ws The workset to iterate
+ * @p v A variable to put the current value in
+ * @p i An integer for internal use
+ */
+#define workset_foreach(ws, v, i) for(i=0; \
+ v=(i < ws->len) ? ws->vals[i].irn : NULL, i < ws->len; \
+ ++i)
#define workset_set_time(ws, i, t) (ws)->vals[i].time=t
#define workset_set_length(ws, length) (ws)->len = length
#define workset_get_val(ws, i) ((ws)->vals[i].irn)
#define workset_sort(ws) qsort((ws)->vals, (ws)->len, sizeof((ws)->vals[0]), loc_compare);
+typedef struct _block_info_t {
+ workset_t *ws_start, *ws_end;
+} block_info_t;
+
+
+static INLINE void *new_block_info(struct obstack *ob) {
+ block_info_t *res = obstack_alloc(ob, sizeof(*res));
+ res->ws_start = NULL;
+ res->ws_end = NULL;
+
+ return res;
+}
+
+#define get_block_info(blk) ((block_info_t *)get_irn_link(blk))
+#define set_block_info(blk, info) set_irn_link(blk, info)
static int is_mem_phi(const ir_node *irn, void *data) {
workset_t *sws;
ir_node *blk = get_nodes_block(irn);
DBG((dbg, DBG_SPILL, "Is %+F a mem-phi?\n", irn));
- sws = ((block_info_t *) get_irn_link(blk))->ws_start;
+ sws = get_block_info(blk)->ws_start;
DBG((dbg, DBG_SPILL, " %d\n", !workset_contains(sws, irn)));
return !workset_contains(sws, irn);
}
/**
- * Collects all values live-in at block @p blk and all phi results in this block.
- * Then it adds the best values (at most n_regs) to the blocks start_workset.
- * The phis among the remaining values get spilled: Introduce psudo-copies of
- * their args to break interference and make it possible to spill them to the
- * same spill slot.
+ * @return The distance to the next use
+ * Or 0 if irn is an ignore node
*/
-static void compute_block_start_info(ir_node *blk, void *env) {
- belady_env_t *bel = env;
- block_info_t *blk_info;
- ir_node *irn, *first;
- irn_live_t *li;
- int i, count, ws_count;
- loc_t loc, *starters;
- ir_graph *irg = get_irn_irg(blk);
- struct obstack ob;
- obstack_init(&ob);
+static INLINE unsigned get_distance(belady_env_t *bel, const ir_node *from, unsigned from_step, const ir_node *def, int skip_from_uses)
+{
+ arch_irn_flags_t fl = arch_irn_get_flags(bel->arch, def);
+ unsigned dist = be_get_next_use(bel->uses, from, from_step, def, skip_from_uses);
- /* Get all values living at the block start */
- DBG((dbg, DBG_START, "Living at start of %+F:\n", blk));
- first = sched_first(blk);
- count = 0;
- sched_foreach(blk, irn)
- if (is_Phi(irn) && arch_get_irn_reg_class(bel->arch, irn, -1) == bel->cls) {
- loc.irn = irn;
- loc.time = be_get_next_use(bel->uses, first, 0, irn, 0);
- obstack_grow(&ob, &loc, sizeof(loc));
- DBG((dbg, DBG_START, " %+F:\n", irn));
- count++;
- } else
- break;
+ if(!USES_IS_INIFINITE(dist) && (fl & (arch_irn_flags_ignore | arch_irn_flags_dont_spill)) != 0)
+ return 0;
- live_foreach(blk, li)
- if (live_is_in(li) && arch_get_irn_reg_class(bel->arch, li->irn, -1) == bel->cls) {
- loc.irn = (ir_node *)li->irn;
- loc.time = be_get_next_use(bel->uses, first, 0, li->irn, 0);
- obstack_grow(&ob, &loc, sizeof(loc));
- DBG((dbg, DBG_START, " %+F:\n", irn));
- count++;
- }
- starters = obstack_finish(&ob);
-
- /* Sort all values */
- qsort(starters, count, sizeof(starters[0]), loc_compare);
-
- /* Create the start workset for this block. Copy the best ones from starters */
- blk_info = obstack_alloc(&bel->ob, sizeof(*blk_info));
- set_irn_link(blk, blk_info);
-
- ws_count = MIN(count, bel->n_regs);
- blk_info->ws_start = new_workset(&bel->ob, bel);
- workset_bulk_fill(blk_info->ws_start, ws_count, starters);
-
- /* Spill the phis among the remaining values */
- for (i=ws_count; i<count; ++i) {
- int o, max;
-
- irn = starters[i].irn;
- if (!is_Phi(irn) || get_nodes_block(irn) != blk)
- continue;
-
- DBG((dbg, DBG_START, "For %+F:\n", irn));
-
- for (max=get_irn_arity(irn), o=0; o<max; ++o) {
- ir_node *arg = get_irn_n(irn, o);
- ir_node *pred_block = get_Block_cfgpred_block(get_nodes_block(irn), o);
- ir_node *cpy = new_Copy(bel->factory, bel->cls, irg, pred_block, arg);
- DBG((dbg, DBG_START, " place a %+F of %+F in %+F\n", cpy, arg, pred_block));
- sched_add_before(pred_block, cpy);
- set_irn_n(irn, o, cpy);
- }
- }
-
- obstack_free(&ob, NULL);
+ return dist;
}
/**
- * Performs the actions neccessary to grant the request that:
+ * Performs the actions necessary to grant the request that:
* - new_vals can be held in registers
* - as few as possible other values are disposed
* - the worst values get disposed
*/
static void displace(belady_env_t *bel, workset_t *new_vals, int is_usage) {
ir_node *val;
- int i, len, max_allowed, demand;
+ int i, len, max_allowed, demand, iter;
workset_t *ws = bel->ws;
ir_node **to_insert = alloca(bel->n_regs * sizeof(*to_insert));
* 1. Identify the number of needed slots and the values to reload
*/
demand = 0;
- workset_foreach(new_vals, val) {
+ workset_foreach(new_vals, val, iter) {
/* mark value as used */
if (is_usage)
pset_insert_ptr(bel->used, val);
}
DBG((dbg, DBG_DECIDE, " demand = %d\n", demand));
-
/*
* 2. Make room for at least 'demand' slots
*/
if (len > max_allowed) {
/* get current next-use distance */
for (i=0; i<ws->len; ++i)
- workset_set_time(ws, i, be_get_next_use(bel->uses, bel->instr, bel->instr_nr, workset_get_val(ws, i), !is_usage));
+ workset_set_time(ws, i, get_distance(bel, bel->instr, bel->instr_nr, workset_get_val(ws, i), !is_usage));
/* sort entries by increasing nextuse-distance*/
workset_sort(ws);
before its first usage, remove it from start workset */
for (i=max_allowed; i<ws->len; ++i) {
ir_node *irn = ws->vals[i].irn;
+
if (!pset_find_ptr(bel->used, irn)) {
ir_node *curr_bb = get_nodes_block(bel->instr);
- workset_t *ws_start = ((block_info_t *) get_irn_link(curr_bb))->ws_start;
+ workset_t *ws_start = get_block_info(curr_bb)->ws_start;
workset_remove(ws_start, irn);
DBG((dbg, DBG_DECIDE, " dispose %+F dumb\n", irn));
workset_bulk_insert(bel->ws, demand, to_insert);
}
+static void belady(ir_node *blk, void *env);
+
+/**
+ * Collects all values live-in at block @p blk and all phi results in this block.
+ * Then it adds the best values (at most n_regs) to the blocks start_workset.
+ * The phis among the remaining values get spilled: Introduce psudo-copies of
+ * their args to break interference and make it possible to spill them to the
+ * same spill slot.
+ */
+static block_info_t *compute_block_start_info(ir_node *blk, void *env) {
+ belady_env_t *bel = env;
+ ir_node *irn, *first;
+ irn_live_t *li;
+ int i, count, ws_count;
+ loc_t loc, *starters;
+ ir_graph *irg = get_irn_irg(blk);
+ struct obstack ob;
+ block_info_t *res = get_block_info(blk);
+
+ /* Have we seen this block before? */
+ if (res)
+ return res;
+
+ /* Create the block info for this block. */
+ res = new_block_info(&bel->ob);
+ set_block_info(blk, res);
+
+
+ /* Get all values living at the block start sorted by next use*/
+ obstack_init(&ob);
+
+ DBG((dbg, DBG_START, "Living at start of %+F:\n", blk));
+ first = sched_first(blk);
+ count = 0;
+ sched_foreach(blk, irn)
+ if (is_Phi(irn) && arch_get_irn_reg_class(bel->arch, irn, -1) == bel->cls) {
+ loc.irn = irn;
+ loc.time = get_distance(bel, first, 0, irn, 0);
+ obstack_grow(&ob, &loc, sizeof(loc));
+ DBG((dbg, DBG_START, " %+F:\n", irn));
+ count++;
+ } else
+ break;
+
+ live_foreach(blk, li)
+ if (live_is_in(li) && arch_get_irn_reg_class(bel->arch, li->irn, -1) == bel->cls) {
+ loc.irn = (ir_node *)li->irn;
+ loc.time = get_distance(bel, first, 0, li->irn, 0);
+ obstack_grow(&ob, &loc, sizeof(loc));
+ DBG((dbg, DBG_START, " %+F:\n", irn));
+ count++;
+ }
+
+ starters = obstack_finish(&ob);
+ qsort(starters, count, sizeof(starters[0]), loc_compare);
+
+
+ /* If we have only one predecessor, we want the start_set of blk to be the end_set of pred */
+ if (get_Block_n_cfgpreds(blk) == 1 && blk != get_irg_start_block(get_irn_irg(blk))) {
+ ir_node *pred_blk = get_Block_cfgpred_block(blk, 0);
+ block_info_t *pred_info = get_block_info(pred_blk);
+
+ /* if pred block has not been processed yet, do it now */
+ if (! pred_info) {
+ belady(pred_blk, bel);
+ pred_info = get_block_info(pred_blk);
+ }
+
+ /* now we have an end_set of pred */
+ assert(pred_info->ws_end && "The recursive call (above) is supposed to compute an end_set");
+ res->ws_start = workset_clone(&bel->ob, pred_info->ws_end);
+
+ } else
+
+ /* Else we want the start_set to be the values used 'the closest' */
+ {
+ /* Copy the best ones from starters to start workset */
+ ws_count = MIN(count, bel->n_regs);
+ res->ws_start = new_workset(&bel->ob, bel);
+ workset_bulk_fill(res->ws_start, ws_count, starters);
+ }
+
+
+ /* The phis of this block which are not in the start set have to be spilled later.
+ * Therefore we add temporary copies in the pred_blocks so the spills can spill
+ * into the same spill slot.
+ * After spilling these copies get deleted. */
+ for (i=workset_get_length(res->ws_start); i<count; ++i) {
+ int o, max;
+
+ irn = starters[i].irn;
+ if (!is_Phi(irn) || get_nodes_block(irn) != blk)
+ continue;
+
+ DBG((dbg, DBG_START, "For %+F:\n", irn));
+
+ for (max=get_irn_arity(irn), o=0; o<max; ++o) {
+ ir_node *arg = get_irn_n(irn, o);
+ ir_node *pred_block = get_Block_cfgpred_block(get_nodes_block(irn), o);
+ ir_node *cpy = be_new_Copy(bel->cls, irg, pred_block, arg);
+ pset_insert_ptr(bel->copies, cpy);
+ DBG((dbg, DBG_START, " place a %+F of %+F in %+F\n", cpy, arg, pred_block));
+ sched_add_before(pred_block, cpy);
+ set_irn_n(irn, o, cpy);
+ }
+ }
+
+ obstack_free(&ob, NULL);
+ return res;
+}
+
+
/**
* For the given block @p blk, decide for each values
* whether it is used from a register or is reloaded
belady_env_t *bel = env;
workset_t *new_vals;
ir_node *irn;
-#ifdef SINGLE_START_PROJS
- ir_node *start_blk = get_irg_start_block(get_irn_irg(blk));
-#endif
- block_info_t *blk_info = get_irn_link(blk);
+ int iter;
+ block_info_t *blk_info;
+
+ /* Don't do a block twice */
+ if (get_block_info(blk))
+ return;
+
+ /* get the starting workset for this block */
+ blk_info = compute_block_start_info(blk, bel);
DBG((dbg, DBG_DECIDE, "\n"));
DBG((dbg, DBG_DECIDE, "Decide for %+F\n", blk));
workset_copy(bel->ws, blk_info->ws_start);
- DBG((dbg, DBG_WSETS, "Initial start workset for %+F:\n", blk));
- workset_foreach(bel->ws, irn)
+ DBG((dbg, DBG_WSETS, "Start workset for %+F:\n", blk));
+ workset_foreach(bel->ws, irn, iter)
DBG((dbg, DBG_WSETS, " %+F\n", irn));
/* process the block from start to end */
assert(workset_get_length(bel->ws) <= bel->n_regs && "Too much values in workset!");
-#ifdef SINGLE_START_PROJS
- if (is_Phi(irn) ||
- (is_Proj(irn) && blk!=start_blk) ||
- (get_irn_mode(irn) == mode_T && blk==start_blk)) {
- DBG((dbg, DBG_DECIDE, " ...%+F skipped\n", irn));
- continue;
- }
-#else
/* projs are handled with the tuple value.
- * Phis are no real instr (see insert_starters)
+ * Phis are no real instr (see insert_starters())
* instr_nr does not increase */
if (is_Proj(irn) || is_Phi(irn)) {
DBG((dbg, DBG_DECIDE, " ...%+F skipped\n", irn));
continue;
}
-#endif
DBG((dbg, DBG_DECIDE, " ...%+F\n", irn));
/* set instruction in the workset */
/* Remember end-workset for this block */
blk_info->ws_end = workset_clone(&bel->ob, bel->ws);
- DBG((dbg, DBG_WSETS, "Start workset for %+F:\n", blk));
- workset_foreach(blk_info->ws_start, irn)
- DBG((dbg, DBG_WSETS, " %+F\n", irn));
DBG((dbg, DBG_WSETS, "End workset for %+F:\n", blk));
- workset_foreach(blk_info->ws_end, irn)
+ workset_foreach(blk_info->ws_end, irn, iter)
DBG((dbg, DBG_WSETS, " %+F\n", irn));
}
static void fix_block_borders(ir_node *blk, void *env) {
workset_t *wsb;
belady_env_t *bel = env;
- int i, max;
+ int i, max, iter, iter2;
DBG((dbg, DBG_FIX, "\n"));
DBG((dbg, DBG_FIX, "Fixing %+F\n", blk));
- wsb = ((block_info_t *)get_irn_link(blk))->ws_start;
+ wsb = get_block_info(blk)->ws_start;
/* process all pred blocks */
for (i=0, max=get_irn_arity(blk); i<max; ++i) {
ir_node *irnb, *irnp, *pred = get_Block_cfgpred_block(blk, i);
- workset_t *wsp = ((block_info_t *)get_irn_link(pred))->ws_end;
+ workset_t *wsp = get_block_info(pred)->ws_end;
DBG((dbg, DBG_FIX, " Pred %+F\n", pred));
- workset_foreach(wsb, irnb) {
+ workset_foreach(wsb, irnb, iter) {
/* if irnb is a phi of the current block we reload
* the corresponding argument, else irnb itself */
if(is_Phi(irnb) && blk == get_nodes_block(irnb))
continue;
/* check if irnb is in a register at end of pred */
- workset_foreach(wsp, irnp)
+ workset_foreach(wsp, irnp, iter2)
if (irnb == irnp)
goto next_value;
* Removes all used reloads from bel->reloads.
* The remaining nodes in bel->reloads will be removed from the graph.
*/
-static void rescue_used_reloads_and_remove_copies(ir_node *irn, void *env) {
+static void rescue_used_reloads(ir_node *irn, void *env) {
pset *rlds = (pset *)env;
if (pset_find_ptr(rlds, irn))
pset_remove_ptr(rlds, irn);
+}
+
+/**
+ * Removes all copies introduced for phi-spills
+ */
+static void remove_copies(belady_env_t *bel) {
+ ir_node *irn;
+ for (irn = pset_first(bel->copies); irn; irn = pset_next(bel->copies)) {
+ ir_node *src, *user;
- /* remove copies introduced for phi-spills */
- if (be_is_Copy(irn)) {
- ir_node *src, *spill;
+ assert(be_is_Copy(irn));
assert(get_irn_n_edges(irn) == 1 && "This is not a copy introduced in 'compute_block_start_info()'. Who created it?");
- spill = get_irn_edge(get_irn_irg(irn), irn, 0)->src;
- assert(be_is_Spill(spill) && "This is not a copy introduced in 'compute_block_start_info()'. Who created it?");
+ user = get_irn_edge(get_irn_irg(irn), irn, 0)->src;
- src = get_irn_n(irn, 0);
- set_irn_n(spill, 0, src);
+ src = be_get_Copy_op(irn);
+ set_irn_n(user, 0, src);
}
}
* Finds all unused reloads and remove them from the schedule
* Also removes spills if they are not used anymore after removing reloads
*/
-static void remove_copies_and_unused_reloads(ir_graph *irg, belady_env_t *bel) {
+static void remove_unused_reloads(ir_graph *irg, belady_env_t *bel) {
ir_node *irn;
- irg_walk_graph(irg, rescue_used_reloads_and_remove_copies, NULL, bel->reloads);
+ irg_walk_graph(irg, rescue_used_reloads, NULL, bel->reloads);
for(irn = pset_first(bel->reloads); irn; irn = pset_next(bel->reloads)) {
ir_node *spill;
DBG((dbg, DBG_SPILL, "Removing %+F before %+F in %+F\n", irn, sched_next(irn), get_nodes_block(irn)));
- spill = get_irn_n(irn, 0);
+ if (be_is_Reload(irn))
+ spill = get_irn_n(irn, be_pos_Reload_mem);
/* remove reload */
set_irn_n(irn, 0, new_Bad());
sched_remove(irn);
- /* if spill not used anymore, remove it too
- * test of regclass is necessary since spill may be a phi-M */
- if (get_irn_n_edges(spill) == 0 && bel->cls == arch_get_irn_reg_class(bel->arch, spill, -1)) {
- set_irn_n(spill, 0, new_Bad());
- sched_remove(spill);
+ if (be_is_Reload(irn)) {
+ /* if spill not used anymore, remove it too
+ * test of regclass is necessary since spill may be a phi-M */
+ if (get_irn_n_edges(spill) == 0 && bel->cls == arch_get_irn_reg_class(bel->arch, spill, -1)) {
+ set_irn_n(spill, 0, new_Bad());
+ sched_remove(spill);
+ }
}
}
}
void be_spill_belady(const be_chordal_env_t *chordal_env) {
belady_env_t bel;
- dbg = firm_dbg_register("ir.be.spillbelady");
- firm_dbg_set_mask(dbg, DEBUG_LVL);
+ FIRM_DBG_REGISTER(dbg, "ir.be.spillbelady");
/* init belady env */
obstack_init(&bel.ob);
- bel.factory = chordal_env->main_env->node_factory;
- bel.arch = chordal_env->main_env->arch_env;
- bel.cls = chordal_env->cls;
- bel.n_regs = arch_register_class_n_regs(bel.cls);
- bel.ws = new_workset(&bel.ob, &bel);
- bel.uses = be_begin_uses(chordal_env->irg, chordal_env->main_env->arch_env, bel.cls);
- bel.senv = be_new_spill_env(dbg, chordal_env, is_mem_phi, NULL);
- bel.reloads = pset_new_ptr_default();
+ bel.arch = chordal_env->birg->main_env->arch_env;
+ bel.cls = chordal_env->cls;
+ bel.n_regs = arch_register_class_n_regs(bel.cls);
+ bel.ws = new_workset(&bel.ob, &bel);
+ bel.uses = be_begin_uses(chordal_env->irg, chordal_env->birg->main_env->arch_env, bel.cls);
+ bel.senv = be_new_spill_env(chordal_env, is_mem_phi, NULL);
+ DEBUG_ONLY(be_set_spill_env_dbg_module(bel.senv, dbg);)
+ bel.reloads = pset_new_ptr_default();
+ bel.copies = pset_new_ptr_default();
+
+ DBG((dbg, LEVEL_1, "running on register class: %s\n", bel.cls->name));
/* do the work */
- irg_block_walk_graph(chordal_env->irg, compute_block_start_info, NULL, &bel);
- irg_block_walk_graph(chordal_env->irg, belady, NULL, &bel);
+ be_clear_links(chordal_env->irg);
+ irg_block_walk_graph(chordal_env->irg, NULL, belady, &bel);
irg_block_walk_graph(chordal_env->irg, fix_block_borders, NULL, &bel);
be_insert_spills_reloads(bel.senv, bel.reloads);
- remove_copies_and_unused_reloads(chordal_env->irg, &bel);
-
+ remove_unused_reloads(chordal_env->irg, &bel);
+ remove_copies(&bel);
/* clean up */
del_pset(bel.reloads);
projects / libfirm / blobdiff